Method of producing tufted carpets



March 8, 1966 A sc w -rz ETAL 3,238,595

METHOD OF PRODUCING TUFTED CARPETS Filed NOV- 15. 1961 pILE 5,951-5400/16- ZNDBGCKING 9 Ti. E |9 INVENTORS #49040 A. Scmvaprz BY Mwow L.SA/zy Patented Mar. 8, 1966 METHOD OF PRODUCING TUFTED CARPETS Harold A.Schwartz, Winstead, Conn., and Harold L.

Sain, Hazelhurst, Ga., assignors, by mesne assignments,

to Patchogue-Plyinouth Company, New York, N.Y., a

joint venture Filed Nov. 15, 1961, Ser. No. 152,562 3 Claims. (CI.28-74) The present invention relates generally to tufted carpets andmore particularly to improved backings therefor and to methods forutilizing such backings in the manufacture of tufted carpets.

Tufted fabrics, such as rugs, carpets, draperies and the like aremanufactured by threading pile yarns through a ready-made woven backingto form pile loops. Backings commonly employed in tufted fabrics aremade of woven material such as cot-ton duck or woven jute fibres. In thecase of tufted carpets, a coating of latex is applied to the back whichacts to lock the tufts to the backing fabric, to stiffen it and to makeit skid-resistant.

In the manufacturing process, the woven backing is fed through amultiple-needle tufting machine. A row of needles carrying the pileyarns pass through the spaces in the backing and as the needles arewithdrawn from the backing, looper members serve to hold the insertedyarns, thereby forming pile loops which project beyond the face of thebacking. In the completed fabric the crests of the loops may remainconnected or be severed, depending on whether a short loop pile or a cutpile fabric is desired.

The nature of the backing incorporated in the tufted fabric is asignificant factor in determining the wearing and handling qualities ofthe finished product. Cotton duck, for example, is relatively light inweight and lacking in body. As a consequence, rugs fabricated with acotton duck backing have a tendency to curl and are structurallyunstable. These disadvantages also to some extent characterize rugs madewith jute backings, the finished fabric having an excessively soft feelor handle. For the rug to lie flat on the floor it is essential that itpossess a degree of stiffness so as to resist kick-up and curling. Withconventional backings, insufficient body is imparted to the rug and therug has low resistance to buckling. Moreover, existing backing materialsare highly absorbent and act to take on undue amounts of latex or otherwater-insoluble adhesives used to bond the pile yarn to the backing,thereby adding materially to pro duction costs.

Also to betaken into account in evaluating the qualities of a wovenbacking is the ease with which the wrap and filler yarns are displacedby the thrust of the looping needles through the pores or interstices ofthe material. With conventional backings there is poor slippage betweenthe warp and filler fibers and substantial resistance is offered to therapid reciprocal movement of the needles. Such friction producesexcessive heating of the needles with an attendant loss of temper. As aresult, the needles require frequent replacement.

One may minimize needle friction as well as needle deflection by usingbackings having a loose, open-weave construction. Since these backingsare easily penetrated, they have less of a tendency to deflect thetut-ting needles. Such deflection gives rise to broken backing yarns,-irregular tuft height and pattern distortion. However, while needleefficiency is improved with a loose backing weave, the resultant carpetlacks proper density and has a somewhat skimpy appearance.

In fabricating tufted carpets, the conventional practice is to apply acoating of latex to the backing to bind the tufts thereof. It is alsocustomary to laminate a scrim or second backing to the carpet, the firstbacking being first sized with a coating of water-based latex, the scrimthen being bonded to the backing by a second coating of latex. Thisprocess has a number of drawbacks. To begin with, latex'is relativelyexpensive. Furthermore, in applying it to the back of the carpet, someof the latex may smear onto the surface, thereby creating seconds. Also,in order to evaporate the water from the latex, large dryers arenecessary, further adding to production costs.

In view of the foregoing, it is the main object of this invention toprovide tufted fabrics of superior construction utilizing a novelbacking material.

Also an object of the invention is to provide a new method offabricating tufted carpet and the like wherein needle deflection isminimized during the tufting operation to increase tufting efiiciency,and yet the final product is of good density with improved tuft bind.

It is still another object of the invention to provide a method offabricating a tufted carpet wherein unusual patterning effects may beobtained by selectively varying the density of the ultimate product.

A further object of this invention is to provide a method of laminatinga scrim to the backing of a tufted carpet without the use of latex andwithout the need for a subsequent drying operation.

Briefly stated, these objects are accomplished by the use of a backingfor a tufted carpet which is composed in whole or in part ofheat-shrinkable thermoplastic yarns. The backing is so woven orotherwise formed in a manner whereby the resultant fabric presents arather loose and easily penetrated structure, thereby facilitating theneedling of the fabric. In tuft binding of the carpet as by means oflatex, the backing is subjected to elevated temperatures causing thebacking to shrink, thereby to improve the density of the fabric. Byvarying the degree of shrinkage, it is also possible to create noveldesign effects.

In lieu of latex, the invention also contemplates the use of a scrim orsecond backing having a coating on one side of thermoplastic resin. Infinishing, this coating as well as the thermoplastic backing on thetufted carpet is heated, whereby the coating is rendered viscous whilethe backing is caused to shrink, the scrim thereby being laminated tothe back-ing to provide a double backed tufted carpet of superiorquality.

For a better understanding of the invention as well as other objects andfurther features thereof, reference is made to the following detaileddescription to be read in conjunction with the accompanying drawing,wherein like components in the views are designated by like referencenumerals.

In the drawing:

FIG. 1 is a sectional view of a tufted carpet in accordance with theinvention.

FIG. 2 is a schematic view of a system for fabricating a carpet inaccordance with the invention,.and

FIG. 3 is a plan view of another embodiment of a tufted carpet inaccordance with the invention, the structure being broken away to showthe various layers thereof.

Referring now to FIG. 1, a tufted fabric in accordance with theinvention includes a preformed backing constituted by longitudinallyextending warp threads 10 and transversely extending weft or fillerthreads 11. The warp and weft threads are loosely interwoven in anyknown manner on a loom. While a woven backing is shown,

3 it is to be understood that the backing may be knitted or otherwiseformed. Tufted into the backing is a pile yarn 12 which may be ofcotton, wool, or any suitable natural or synthetic fiber.

The yarn is introduced in the usual manner by feeding the backing webthrough a tufting machine wherein rows of needles carrying the yarnspass them through the interstices of the backing to form chains of pileloops 13 projecting above the face of the backing, the pile loops beinglinked by connecting loops 14 closely drawn against the under surface ofthe backing.

The under surface of the backing is covered with a relatively thinanchoring coating 15 of a water-insoluble adhesive, such as latex. Theadhesive is applied in a fluid state and flows freely into the spacesbetween the warp and weft threads to define a film-like coating whichbonds the connecting loops to the backing threads. This latex coating isthen cured, or if other forms of adhesive are employed, the coating isallowed to harden and set as required The backing fabric is Woven orotherwise formed of heat shrinkage thermoplastic yarns or combinationsor composites of thermoplastic yarns with other textile yarns, as, forexample, cotton, jute, rayon and paper. The thermoplastic yarns are ofthe type having softening or distorting characteristics which lendthemselves to shrinkage control in a temperature range about 150 F. to450 F.

Examples of suitable thermoplastic yarns are yarns manufactured invarious densities from polypropylene resin, polyamide resin, polyesterresin and polyacrylic resin. Vinyl fibers, such as dynel, may be used(60% vinyl chloride, 40% acrylonitrite) having a 45% shrinkage in 300 F.air, or polyethylene fibers of the high density type having a shrinkageof 12 to 18% in 240 F. air. Also, saran having a shrinkage of 60% in 350F. air is usable.

The backing fabric, utilizing thermoplastic yarns or combinationsthereof, is so formed as to present a rather loose structure havingeasily penetrated well-defined interstices. This eliminates or minimizesthe usual problems encountered in needling the backing with tuftingyarns. In the finishing operation, when latex is applied to the backingto tuft bind the individual carpet tufts, the carpet is subjected to airtemperatures ranging from 225 450 F. The degree of shrinkage will ofcourse depend on the nature of the thermoplastic material used and thetemperature range applied. It is therefore possible to vary the degreeof shrinkage selectively to create novel design effects, this beingaccomplished by introducing into the carpet predetermined areas ofgreater or lesser yarn density. Such effects have not heretofore beenattainable with tufted carpets and one may produce a wide variety ofpatterns formed by sectors of differing density.

Thus the invention, by providing a relatively open backing structure,improves tufting efificiency and eliminates pattern distortion resultingfrom a too closely woven backing fabric. It also prevents excessivefloats or broken yarns which protrude and show up in the pile yarns.After being subjected to elevated temperatures in the finishingoperation, improved tuft bind is realized and the invention also enablesdensity control to produce novel patterning effects.

While the above results may be accomplished with conventional latexfinishing techniques, such techniques, as pointed out previously, havecertain commercial drawbacks. In accordance with another aspect of theinvention, a double backed tufted rug is provided, as shown in FIG. 3,with a thermoplastic backing 16, of the type disclosed in conjunctionwith FIG. 1 having a pile 17 tufted therein, the backing having a scrim18 laminated thereon by means of an adhesive coating 19 in the form of athermoplastic resin whose composition is compatible with thethermoplastic yarns in the main backing.

The resin coating is applied in liquid form to scrim 18, which may beformed of closely woven paper yarns, by means of conventional rollercoating techniques. Suitable resins for this purpose having propersoftening points or molecular weights are petroleum resins such asPiccopale, polyvinyl chloride and copolymers thereof, polyvinylidenechloride and copolymers thereof, resin and resin derivatives such asVinsol, Dresinol and Hercolyn, polybutene resins such as Vistac andstyrenebutadiene resins and copolymers thereof.

The scrim is coated with the resin in solution and dried to provide anon-tacky coated scrim. When the scrim is to be laminated to the carpetbacking, it is simply heated to the softening point of the coating andcombined under pressure with the backing. No preliminary back coating orlatexing operation is entailed. Among the advantages of this operationare a saving in adhesive and latex costs (hot melt resins are cheaper),ease of application and lower laminating costs (no dryers arenecessary), and the fact that no adhesive will or can smear onto thefront surface of the carpet.

While the coated scrim may be applied to the back of a conventionaltufted fabric, there are distinct advantages in using it in conjunctionwith a fabric having a thermoplastic backing as above described, for theheat necessary to soften the coating on the scrim may also function toshrink the thermoplastic backing.

Thus, as shown in FIG. 2, the scrim 18 having the coating 19 is drawn inweb form from a supply roll 20. The tufted fabric also in web form isdrawn from supply roll 21, the coating 19 of the scrim being juxtaposedwith the backing 16 of the rug in rolls 22. The two webs are then fedinto a heating chamber 23 provided with infra-red heaters 24 or othersuitable means to raise the temperature to the desired level sufficientto shrink the backing fabric and to soften the resin coating. Combiningrolls 25 are provided to subject the two webs to pressure to effectlamination therebetween. Belts may be used instead of rolls for thispurpose. The combined structure is wound up on take-up roll 26.

To insure effective lamination, it is preferable that the resin coatingon the scrim be of the same family as the thermoplastic yarns in thebacking and hence compatible therewith. For example, if the yarns are ofthe vinyl family, the resin should be selected accordingly.

Thus, while there has been shown what are considered to be preferredembodiments of the invention, it will be understood that many changesand modifications may 'be made therein without departing from theessential spirit of the invention as defined in the appended claims.

What is claimed is:

1. The method of fabricating a tufted carpet comprising the steps ofneedling tufting yarns into a backing formed at least in part ofheat-shrinkable thermoplastic yarn, and laminating a scrim to saidbacking having a hot melt coating thereon by simultaneously heating saidcoating and said backing to shrink said backing and render said coatingviscous to effect a bonding action.

2. The method, as set forth in claim 1, wherein said coating is of hotmelt, resinous material compatible with said thermoplastic material.

3. The method of producing a double-backed tufted carpet, comprising thesteps of needling tufting yarn into a primary backing formed at least inpart of heat-shrinkable thermoplastic yarn, coating a secondary backingwith a thermoplastic resin in solution form and drying same to provide anon-tacky coating, and laminating the coated side of said secondarybacking to said primary backing by subjecting said backingssimultaneously to heat and pressure to cause said coating to soften andto cause said primary backing to shrink, whereby said shrunken primarybacking and said secondary backing are interbonded.

(References on following page) References Cited by the Examiner UNITEDSTATES PATENTS Davison 2874 Castles 2874 Miller 161--66 Young et a1.2874 Dow et a1 2874 X Foster 2872 Petroske 2880 6 2,999,297 9/ 1961Schwartz 2874 X 3,017,847 1/1962 Keen 2872 X 3,166,465 1/ 1965 Rahmes2874 X FOREIGN PATENTS 624,609 7/1961 Canada. 727,591 4/ 1955 GreatBritain.

DONALD W. PARKER, Primary Examiner.

RUSSELL C. MADER, Examiner.

1. THE METHOD OF FABRICATING A TUFTED CARPET COMPRISING THE STEPS OFNEEDLING TUFTING YARNS INTO A BACKING FORMED AT LEAST IN PART OFHEAT-SHRINKABLE TERMOPLASTIC YARN, AND LAMINATING A SCRIM TO SAIDBACKING HAVING A HOT MELT COATING THEREON BY SIMULTANEOUSLY HEATING SAIDCOATING AND SAID BACKING TO SHRINK SAID BACKING AND RENDER SAID COATINGVISCOUS TO EFFECT A BONDING ACTION.